Hydraulic well jar



Oct. 18, 1955 w. STORM HYDRAULIC WELL. JAR

4 Sheets-Sheet 1 Filed Feb. 14, 1952 W Jform INVENTOR Lynn ZZQKWJATTORNEY Oct. 18, 1955 1.. w. STORM HYDRAULIC WELL JAR 4 Sheets-Sheet 2Filed Feb. 14, 1952 [507/7 l V. Jfo/"m l N VEN TOR.

A 7 TOR/V5) Oct. 18, 1955 w STORM 2,721,056

HYDRAULIC WELL JAR TTOR/VE Y United States Patent HYDRAULIC WELL JARLynn W. Storm, Houston, Tex.

Application February 14, 1952, Serial No. 271,473

7 Claims. (Cl. 25527) This invention relates to a hydraulic well jar,and more particularly to a jarring tool for use in the removal of astuck object in the bore of a well and in which a liquid is employed forcontrolling the action of the tool.

The invention finds particular application in jarring tools of thehydraulic type, having inner and outer concentrically arranged tubularparts movable longitudinally relative to each other and forming betweenthem a closed fluid chamber. The outer part, or barrel, in jars of thistype, is provided with a portion of restricted internal diameter withinthe fluid chamber, and the inner part, or mandrel, carries a pistonwhich is movable into and out of the restriction, the annulus of thepiston being slightly smaller than the internal diameter of therestriction to permit the flow of liquid past the piston as the pistonmoves in the restriction.

In the use of jars of this type, the outer part, or barrel, may beconnected to an operating string, while the inner part, or mandrel, maybe connected to an object stuck in the bore of a well, and upon upwardor downward movement of the operating string, the parts are movedlongitudinally relative to each other, the liquid in the chamber flowingpast the piston during such movement. Upon movement of the piston intothe restriction, however, the flow of liquid past the piston isrestricted, so that further relative movement of the parts takes placevery slowly, resulting in the development of tension or compression inthe operating string, depending upon whether the same is being movedupwardly or downwardly. As soon as the piston moves out of therestriction, however, the relative movement of the parts is no longerrestrained, and the parts move suddenly to the limit of their relativemovement to produce a jarring action.

Jars of this type may be used to produce a jarring action eitherupwardly or downwardly, and in the event it is desired to operate such ajar to carry out a jarring action in one direction only, either upwardlyor downwardly, the difliculty is encountered that the parts must bemoved relative to each other in the opposite direction to bring them toposition to initiate a jarring stroke, and such return movement of theparts can take place only very slowly as the piston makes its returnmovement in the restriction, thus greatly slowing the jarring operation.

In the use of such tools the fluid chamber is customarily filledcompletely with a suitable liquid, such as oil, and any loss of liquiddue to leakage results in the entrance of air into the chamber, whichmay adversely affect the operation of the tool, in that it interfereswith the hydraulic action of the same, and continued operation of thetool in such condition often results in the formation of an undesirableemulsion with the oil. The construction of such a tool having a fluidchamber which is adapted to be completely filled with liquid alsopresents a diflicult problem in that the inner and outer parts must beso formed that no change in the volume of the fluid chamber will takeplace upon relative longi- ICC tudinal movement of the parts. A slightvariation in the volume of the fluid chamber, brought about uponrelative longitudinal movement of the parts, may result in theproduction of a tool which does not operate properly or in which thepacking between the moving parts is subjected to excessive pressures,causing leakage of the liquid, or permitting the entrance of air intothe fluid chamber.

The present invention has for its principal object the provision of ajarring tool of the type referred to in which the above disadvantagesare overcome, and in which means is provided for the relatively rapidmovement of the piston in the restriction, upon relative longitudinalmovement of the inner and outer parts in one direction, in order topermit a rapid movement of the parts to place the tool in condition forjarring operation upon relative movement of the parts in the otherdirection.

Another object of the invention is to provide a jarring tool of thehydraulic type, having inner and outer telescopically arranged tubularparts movable longitudinally relative to each other, and forming betweenthem a closed liquid chamber, the outer parts having a portion ofreduced internal diameter forming a restriction in the chamber, and theinner part carrying a piston whose annulus is slightly smaller than therestriction, there being compressible means within the chamberresponsive to the pressure of the liquid therein, to permit the pistonto have unrestrained movement in the restriction, upon relativelongitudinal movement of the parts in one direction.

Another object of the invention is the provision of a jarring tool ofthe type referred to wherein a compressible fluid is utilized within theliquid chamber which is responsive to pressure developed in the liquidin the chamber to permit relatively unrestricted movement of the pistonin the restriction, upon relative longitudinal movement of the parts inone direction, and means is provided for maintaining the compressiblefluid out or contact with the liquid in the chamber to preventintermingling of the fluid with the liquid.

A further object of the invention is to provide a jarring tool of thehydraulic type, constructed as described above, and embodying meansresponsive to the pressure of the liquid in the fluid chamber, uponrelative longitudinal movement of the parts in one direction, to permitmovement of the piston in the restriction in said one direction moreeasily than in the other direction, said means being eifective to causea flow of liquid through the restriction in the other direction, uponmovement of the piston out of the restriction in said one direction.

Another object of the invention is the provision of a jarring toolconstructed with inner and outer concentrically arranged tubular partsmovable longitudinally relative to each other, and forming between thema closed fluid chamber, the outer part having a portion of reducedinternal diameter forming a restriction within the chamber, and theinner part carrying a piston whose annulus is slightly smaller than saidportion of reduced diameter, there being means in the chamber responsiveto variations in the volume of the chamber at one side of therestriction, to allow the piston to have relatively unrestrictedmovement in one direction in the restriction.

A further object of the invention is the provision of a jarring tool ofthe type referred to, which is of simple design and rugged construction,capable of long Withstanding the severe conditions of use to which suchan object is customarily subjected.

The above and other objects and advantages of the invention will best beunderstood from the following detailed description, constituting aspecification of the same.

7 when taken in conjunction with the annexed drawings,

cross section, of the upper portionof a :jarin accordance with the"invention;

Figure 2A is a fragmentary 'elevational view, partly in cross section,of the lower portion ofthe same;

Figure 3 is a cross-sectional view taken along the line 3-3 of Figure 2,looking in thedirection indicated 'by the arrows;

Figure 4 is across-sectional view taken-along theline of 4-4 of Figure2A, looking inthe direction indicated by the arrows;

Figure 5 is a-fragmentary vertical cross-sectional view on a somewhatenlargedscale, showing details of construction of a-prefe'rred form ofthe invention;

' Figure 6 is a fragmentary elevational view, :partly in cross section,illustrating a somewhat different form of the invention;

Figure Tis a .view similar to that of Figure 6, illustrating anotherformof'the invention;

Figure 8 is a view similar to'that of Figure 5, ing a further differentform of the invention;

Figure 9 is a view similar to that of Figure 2, illustrating afurtherdifferent form of the invention; and

Figure 10 is a view similar to that of Figure 6, illustrating a somewhatmodified form of the invention.

Referring now to the drawings in greater detail, the jar comprisesinner-and outer telescopically arranged'tubular parts indicatedgenerally at 1 and 2, respectively, which parts are movablelongitudinally relative to each other, and form between them a closedfluid chamber 48.

illustrat- The outer part'is conveniently made up of an upper tubularcoupling member 10, and intermediate barrel section 12 and a lowertubular member '14, and the inner part is made up of upper and lowertubular mandrel sections 16 and 18, respectively. The lowerend of thelower'mandrel section 18 is externally threaded, as indicated at 20, forthe attachment thereto of a lower coupling member 22, which is-providedwith an internally threaded box portion, as indicated at 24, by whichthe inner partof'the tool is attached to the upper end of a lowersection 26 of the operating string, or'other device below the jar.

At its upper end the upper'coupling rnemberIlO has an externallythreaded endportion 28, by which this member may be attached to thelower end of a section '30 of an operating'string, and at its lower end'the upper coupling member has a reduced extern'ally'threaded portion32, by which it is threadably attached to the upper end of the barrel12. The lower end of the upper-coupling member is also inwardlythickened, as indicated at 34,'and is provided with inwardlyopening,annular, internal grooves 36, within which sealing means, such as'O-rings 38 are received, to form a fluid tight seal between the uppercoupling member and the upper mandrel section 16. p

The lower tubular member 14 has a reduced, externally threaded, upperend portion 40, by which this member is threadably attached to the lowerend of the barrel 12, and the lower end of the member 14 is inwardlythickened, as indicated at 42, and is provided with'inwa'rdly opening,annular internal grooves 44, for the reception of seal ing means, suchas O-rings 46, which form a fluid tight seal between the member 14 andthe lower mandrel section 18.

'Betweentheinner and outer tubular parts, and extending from the sealingmeans 38 in the upper coupling member to the sealing means 46 inthelowertubular member 14 there is a closed fluid chamber 48, which is normallyintended to be filled with 'asuitable liquid, such as oil. The barrelsection'12 has an-inwafdly thickened portion 4 50, providing .an annularrestriction in the chamber 48, for a purpose later to be made apparent.

The upper and lower mandrel sections 16 and 18 are threadably connectedtogether, as indicated at 52, and the lower mandrel section has anexteriorly thickened annular portion 54, forming an upwardly facingshoulder 56, upon which an annular member 58 is seated, the lower end 60of the upper mandrel section being engageable with the member 58, toretain the same in position on the mandrel. The member 58 isconveniently formed with an internalannular groove 62, for the receptionof suitable *seal'ingme'ans, such as an D ring 64, forming a fluid tightseal between the member .58 and the mandrel.

The member 58 forms a piston onthe mandrel, which is I adapted to moveinto and out of the restriction 50, upon relative longitudinal movementof the inner and outer parts.

With the par'ts'assembled asshown, it will be apparent that uponrelativ'e longitudinal movement of the sinner and outer parts, when thepiston 5'8 enters the restriction 'flow of liquid in thechamber fronione side to -the other :side of the restrictio'n will be restricted, andthe rate of "relative longitudinal :movement between the innerand outerparts will depend' upon the amount-of 'cl'earthe exertion of a downward:force on the operating string will result :in forcing the liquid in thechamber slowly from -one side "of the restriction to the other sidethereof past the piston, thus building up a'cornpressive force in theoperating string while the piston moves slowly through the restriction.As soon asthe piston moves :out of the restriction, however, the liquidin 'thie ch'amber may move freely past the pistongand th'e inn'er and=ou't'er parts may move rapidlyrela'tive to .each other. The piston 58,may, if desired, have a restricted duot 59 le'ading from the upper tothe lower side thereof, as s'e'e'r'r in Figure .2, whereby liquid mayflow fr'o'm 'one side 'of-the piston to the other as the piston moves inthere'st'riction.

The flower'end of th'elower tubular member l'4 'h'as a contact 'face '98on :the outer :part, which is engageable ternal splines 68 fornied onthelowenmandreI'section 18,

whereby relative rotation ofth'e inner' and outer parts is prevented.The exteriorly thickened annular-por'tion :54 ofthe lower mandrelsection 1 8 has a lower face 102, shown in Figure -2, which:i's=engage'able" with the'upper ends 104 of the splines 66 of thebarrel 12 as seen in Figure 2A, -to produce an upward ":jarrin'g actionin the operation of thetool.

As best seen in Figures 2., 3 and '5, the barrel 12 also has an inwardlythickened portion 70, providing an upwardly facing annular shoulder 72,and in the'preferred form of the invention, as :best seen in Figures 2and 5, there is an annular casing 74, preferably formed of metal oro'ther relatively rigid material, surr'ounding 'the'uppermandrels'ection 1'6, Within'the ba'rrel 1 2, and ine'enga'gement withthe shoulder 72 therein. :In order to securely maintain the casingagainst longitudinal movement in the barrel tlie slower end 'surfa'ce'bft'he upper-coupling member 10 may engage the upper surface'ofthe easingto'hold the same againstthe shoulder 72. The casing '14 is of hollowconstruction, and enclosed within the casing there is a hollow member76, in the 'form' of aclosed container of flexible material, filled withcompressible materiahsuch asair. The casing '74 is also 'provided'withopenings 78, communicating with the interior of the casing and also withthe chamber 48, whereby liquid in the chamber may enter the casing.

During the operation of the tool, theexertion'of an upwardpull onthe'operating string will result in *moving the barrel longitudinallyupwardly relative to the mandrel, so that when the piston 53 enters therestriction 59 the flow of liquid in the chamber from one side of thepiston to the other side thereof will be restricted, resulting in abuilding up of tension in the operating string, until the piston movesout of the restriction, whereupon the flow of liquid past the pistonwill be unrestricted and the barrel will move suddenly upwardly relativeto the mandrel, until the lower surface 102 of the piston engages theupper end 194 of the spline 66 of the barrel to cause an upward jarringaction. After the occurrence of an upward jarring action of the tool, asjust described, the operating string may be lowered, whereupon thebarrel 12 will move downwardly relative to the mandrel and the piston 53will move in the opposite direction through the restriction 55 As soonas the piston 58 enters the restriction the fiow of liquid past thepiston is retarded, resulting in a building up of the pressure withinthe fluid chamber above the restriction, which pressure causes liquid topass through the openings 78 in the casing 74, thus compressing thecontainer 76, so that the movement of the piston in the restriction isretarded only by the resistance due to the compression of the container76, and the barrel may readily move downwardly over the mandrel to thelimit of its downward movement relative thereto. Thus the parts may bequickly brought to position to initiate a further jarring operation ofthe tool. As soon as the piston moves out of the restriction on thereturn movement of the parts just described, the pressure built up inthe flexible container 76 will immediately return the liquid through theopening 78 to the fluid chamber, thus immediately restoring the liquidin the chamber to a condition to eiiect another jarring action.

in the form of the invention illustrated in Figure 6, the upper couplingmember is formed with a downwardly extending sleeve-like portion 8!spaced radially inwardly of the barrel 12. At its lower end thesleevelike portion St is externally threaded and has a nut 82 threadedthereon, providing an upwardly facing shoulder 84, opposite the shoulder72 on the barrel. An annular space 86 is formed between the sleeve-likeextension 80 and the barrel 12, which space provides an annularcompartment or cylinder 86, closed at one end and opening at its otherend into the fluid chamber 43, and in this cylinder an annular piston 88is disposed for longitudinal movement. The piston 88 is provided withsuitable packing, as indicated at 92, forming a fluid tight seal betweenthe piston and the inner surface of the barrel 12. A coil spring, 94, orother equivalent resilient member is disposed in the space 86, hearingat one end against the upper coupling member 10, and at the other endagainst the piston 83, to urge the piston toward the shoulders 72 and84. In this form of the invention, any increase in pressure in thechamber above the restriction, upon operation of the tool, will resultin the liquid in the chamber 48 exerting a pressure against the piston88, to move the same longitudinally in the space 86 against the actionof the spring 94.

Upon movement of the barrel 12 to bring the piston 58 above therestriction, the liquid may move freely past the piston, and after thepiston has moved out of the restriction the spring 94 will urge thepiston toward the shoulders 72 and 84, returning liquid to the chamber.

The form of the invention illustrated in Figure 7 is similar to thatshown in Figure 6, but in this case the upper coupling member 10a doesnot have the sleeve-like portion 89 thereon, and the shoulder 72 definesone end of the annular compartment 86a between the upper manrel section16 and the barrel 12. Within the compartment 3612 an annular piston 88ais movably positioned, and suitable sealing means 2a is provided on thepiston to form a fluid-tight seal between the piston and the mandrelsection 16 and between the piston and the barrel 12. A coil spring 94ais also disposed in the compartment 86a which yieldably urges the pistontoward the shoulder 72. This form of the invention is other- 6 wisesubstantially the same as that illustrated in Figure 6, and operates inthe same manner.

In Figure 8 there is illustrated a somewhat modified form of theinvention similar to the form illustrated in Figure 5. In this case,however, the casing 74 is omitted and the flexible hollow container 76ais positioned within the compartment whose ends are defined by the lowerend of the upper coupling member 10 and the shoulder 72 between theupper mandrel section 16 and the barrel 12. In other respects this formof the invention is similar to the form shown in Figure 5, and functionsin the same manner.

A still further embodiment of the invention is illustrated in Figure 9,and in Figure 10 there is shown a somewhat modified form of theembodiment of Figure 9. As seen in Figure 9, the structure of the jar issubstantially the same as that described in connection with Figure 7except that the inwardly thickened portion b of the barrel i2 is ofgreater width than the portion 70 previously described, whereby arelatively wide upwardly facing annular shoulder 72!) is provideddefining the open end of an annular compartment 861; in communicationwith the fluid chamber 43. In this form of the invention an O-ring 1%takes the place of the piston 88a, which O-ring is preferably offlexible material such as rubber, or the like. The operation of thisform of the invention is similar to that already described, the O-ring196 moving upwardly in the compartment 86b against the pressure of theair therein during the movement of the piston 58 in the restriction 5%,as the barrel 12 moves downwardly relative to the mandrel. Likewise, assoon as the piston 58 moves up out of the restriction the pressure ofair in the compartment 86b returns the O-ring to a position inengagement with the shoulder 72b, thus returning the liquid from withinthe compartment to the fluid chamber 43.

The form of the invention illustrated in Figure 10 is like that shown inFigure 7, except that the portion 7% of the barrel is thickened asindicated at 70]) to provide the relatively wide upwardly facingshoulder 72]; with which the O-ring 1% is engageable at the limit of itsoutward movement in the compartment 86b. The O ring 106 in this case isprovided with a back-up ring 1%, and there is a coil spring 94b withinthe compartment 36b which bears at one end upon the back-up ring and atthe other end against the upper coupling member 10b. The spring 9412urges the 0-ring toward the shoulder 725.

This form of the invention is in other respects similar to the formillustrated in Figure 6, and functions in a similar manner.

It will be apparent that the compressible means described may beprovided at either side of the restriction in the chamber, whereby thetool may be adapted for jarring either upwardly or downwardly as may bedesired.

It will also be apparent that the invention, as described above providesa jarring tool having a closed chamber which may be maintained filledwith liquid, in order to secure the maximum efiiciency in the operationof the tool hydraulically, and wherein means is provided forcompensating for variations in the volume of the chamher during theoperation of the tool, so that injury or excessive wear of the packingelements is prevented, as well as leakage of the liquid from the chamberdue to the development of excessive hydraulic pressures or the entranceof air into the chamber past the packing elements in the event of anyincrease in the volume of the chamber due to imperfection in themanufacture of the parts.

The invention has been disclosed in connection with certain specificembodiments of the same, but it will be understood that these areintended by way of illustration only, and that numerous changes can bemade in the construction and arrangement of the various parts, withoutdeparting from theQspirit of the.-invention, or the scope ofi theappended claims...

Having thus clearly shown-and described the invention, what is claimedas new and desired to secure by Letters Patent isl; A'well toolcomprising inner and outer concentrically arranged tubular parts movablelongitudinally relative to. each other, means for connecting one of saidparts to an operating string, meansfor connecting the other of saidpartsto an object stuck in a well bore, said parts forming an annularliquid containing chamber between the parts, a piston on the. inner partin the. chamber, sealing means between the parts at each end of saidchamber, saidouter parthaving a portion of reduced internal diameter inthe chamber. forming a restriction between the ends of the chamber inwhich said piston is adapted to move upon relative longitudinal movementof said inner and router parts, the external diameter of the pistonbeing slightly smaller than the internal diameter of said restriction topermit the flow of liquid from one side of the piston to the other sidethereof as the piston moves in said portion, pressure responsive meansin said chamber on one side of said restriction, including a closedcontainer of flexible material and compressible material filling saidcontainer, said means beingresponsive to variations in thepressure insaid chamber on said one side of said restriction upon, relativelongitudinal movement of said parts to permit movement of the piston inone direction in said restriction against a reduced restraining force.

2. A well tool comprising inner and outer concentrically arrangedtubular parts movable longitudinally relative to each other, means forconnecting one of said parts to an operating string, means forconnecting the other of said parts to an object stuck in a well bore,said parts formingannular liquid filled chamber between the parts, apiston on the inner part in the chamber, sealing means between the partsat each end of said chamber, said outer part havinga portion of reducedinternal diameter forming a restriction between the ends of the chamberin which said piston is adapted to move upon relative longitudinalmovement of said inner and outer parts, the external diameter of thepiston being slightly smaller than the internal diameter of saidrestriction to permit the flow of liquid fromone side of the piston tothe other side thereof as the piston moves in said restriction, means.

connected with the outer part and forming an annular compartment betweensaid inner and outer parts, said compartment being closed at one end andopening at its other end into said chamber, a compressible. fluidinsaid- V callyarranged tubular parts movable longitudinally relative toeach other, means for connecting one of said parts. to an operatingstring, means for connecting the other of said parts to an object stuckin a well bore, said parts forming between them a liquid containingchamber,

a piston on the inner part in the chamber, sealing means a at each endof said chamber between said inner and outer parts, said outer parthaving a portion of reduced internal dimeter forming a restriction inthe chamber in which the piston is adapted to move upon relativelongitudinal movement of said inner and outer parts, the externaldiameter of the piston being slightly smaller than internal diameter. ofsaid restriction to permit the flow of liquid from one side of thepiston to the other side thereof as the piston; moves .in saidrestriction, a compressible fluid in said chamber 01170116 sideof saidrestriction, movable. means. in said chamber separating said fluid fromthe tion to effect compresion of said compressible fluid.

parts formingtbetween them a liquid containing chamber, a piston on theinner partin the chamber, sealing means at each end of said chamberbetween said inner and outer parts, said outer-part having a'portion ofreduced internal diameter forming a restrictionin the chamber in whichthe piston is adapted to move upon relative longitudinal movement ofsaid inner and outer, parts, the'external' diameter of the-piston beingslightly smaller than the internal diameter of said restriction topermit the flow of liquidfrom. one side of the piston to the-other sidevthereof as the piston moves in said restriction, a compressible fluid insaid chamber on. one side of saidrestriction, movable means in thechamber separating said' from the. liquid therein, said meansbeingmovable in one direction upon an increase in pressure in said chamber onone side of said. restriction to compress said fluid,

and in another. direction upon a decrease of pressure in" said chamberonsaid one side of said restriction to permit said fluid to expand,

5. A- well tool comprising inner and outer concentrically arrangedtubular parts. movable longitudinally. relative to each other, means forconnecting one of said parts to an operating string, means forconnecting the other of said parts to an object stuck in a well bore,said parts forming between them a liquid containing chamber, a piston onthe innerpart in the'chamber, said piston having a duct leading fromthe'upper to the lower side thereof, sealing means at each end of saidchamber between said parts, said outer part having a portion of reducedinternal diameter forming a restriction between the ends of the chamberin which the piston is adapted to move upon relative longitudinalmovement of said inner and outer parts, said piston being of a size tosubstantially close said restriction to cause a flow of liquid throughsaid duct from one side of thepiston to the other side thereof as thepiston moves in said restriction, a compressible fluidin said chamberonone side of said restriction, means in said chamber separating saidfluid from the'liquid therein and movable in the chamber in response tochanges in the pressure in said chamber on said one side of said.

7 piston on the. inner, part in the chamber, sealing means at each endof said chamber between said inner and outer parts, said outer parthaving a portion of reducedinternal diameterv forming a restrictionbetween the ends of the chamber and in which the piston is adapted tomove upon relative longitudinal movement of said inner and outer parts,the external diameter of the piston being slightly smaller than theinternal diameter of said restriction to. permit the flowot liquidfromone side of thepiston to the other side thereof as the piston moves insaid restric-' tive to each. other,,means for connecting one, of saidpartsto an operating string, means for connecting the other of saidparts to an object stuck in a well bore, said parts forming between them-a liquid containing chamber, a piston on the inner part in the chamber,sealing means at each end of said chamber between said inner and outerparts, said outer part having a portion of reduced internal diameterforming a restriction between ends of the chamber in which the piston isadapted to move upon relative longitudinal movement of said inner andouter parts, a compressible fluid in said chamber on one side of therestriction, movable means in said chamber separating said fluid fromthe liquid therein and movable in response to an increase of pressure insaid chamber on said one side of said restriction to eifect compressionof said compressible fluid.

References Cited in the file of this patent UNITED STATES PATENT-S1,804,700 Maxwell "May 12, 1931 2,265,431 Kerr -d Dec. 9, 1941 2,364,869Osmun Dec. 12, 1944 10 2,499,695 Storm Mar. 7, 1950

